Ap Psych- Unit 3

Sensation

the detection of physical energy and conversion to neural signals

Perception

the interpretation of sensory info

Bottom Up Processing

the brain receiving signals from sensory organs ( sensation)

Top-Down Processing

information processing guided by higher-level mental processes ( Perception)

Transduction

converting one form of energy into another that our brain can use

Psychophysics

a field of study that studies the relationships between the physical energy we can detect, and its effect on our psychological.

Absolute threshold

the smallest quantity of physical energy that can be detected 50% of the time by an observer.

Subliminal threshold

messages interpreted by the brain that are below the absolute threshold of humans

signal detection theory

predicts how and when we detect the presence of a weak stimulus amid background noise. Assumes there is no single absolute threshold

Difference Threshold

minimum difference between 2 stimuli required for detection 50% of the time.

AKA: Just Noticeable Difference

Weber's Law

For an average person to notice a difference, two stimuli must differ by a constant minimum percentage to be perceived as different.

Sensory Adaptation

The reduction or disappearance of sensory responsiveness that occurs when stimulation is unchanging.

Phototransduction

conversion of light energy into neural impulses that the brain can understand

Wavelength

distance from peak of one wave to peak of the next

Hue ( color)

dimension determined by the wavelength of the light

Blues/purples = ________ wavelengths

short

reds= _________ wavelengths

long

intensity ( brightness)

amount of energy in a wave determined by the amplitude.

The pupil and Iris

constrict or dilate to control light flow

Lens

transparent structure behind the pupil that changes shape to focus images on retina

Accommodation

process by which the eyes lens changes shape to focus near or far objects on the retnia

Nearsightedness

A condition in which nearby objects are seen more clearly than distant objects

Farsightedness

A condition in which faraway objects are seen more clearly than near objects

The retina

Light sensitive inner surface of the eye containing receptor rods and cones and layers of other neurons that process visual information

Cones

Allow us to see color and fine detail; cluster around the Fovea ( retinal center)

Rods

Allow for night and peripheral vision ( not present in the fovea)

Bipolar cells

recieve messages from the photoreceptors and transmit them to Ganglion cells

Ganglion Cells

sends info to the visual cortex through the thalamus

optic nerve

carries neural impulses from the eye to the brain

Blind Spot

There are no receptor cells located where the optic nerve leaves the eye, creating a blind spot

Color constancy

perceiving familiar objects as having consistent color, even if changing illumination alters the wavelengths reflected by the object

the trichromatic theory ( Young and Helmholtz)

retinal receptors are sensitive to 3 colors

Color Vision: Subtraction

If 3 primary colors are mixed, subtraction of all wavelengths occurs and the result is the color black

Color VIsion: Addition

If 3 primary colors are mixed, the wavelengths are added and the result is the color white

opponent-process theory

Receptors and neurons fire in response to certain color waves and are inhibited from firing/responding to others

Feature Detection

Nerve cells in the visual cortex respond to specific features , such as edges, angles, and movement

Paralell Proccessing

Processing of several aspects of a stimulus simultaneously The brain divides a visual scene into subdivisions such as color, depth, form, movement,

Gestalt psychology

When given a cluster of sensation, humans tend to organize view them as a whole rather than their individual parts

Proximity

things that are near each other tend to be grouped together

Closure

when theres a break in an object, the brain perceives the object as continuing in time and space

Similarity

Things that are alike (by size, shape, color, etc.) tend to be perceived as belonging to each other

Continuity

Lines and patterns tend to be percieved as continuing in time and space perceived

Figure and ground

Figure- items that stand out from the rest of the environment

Ground- the background

Depth Perception

the ability to see objects in 3-D although the images that strike the retina are 2-D; allows us to judge distance

Visual Cliff

a laboratory device for testing depth perception in infants and young animals

Monocular Cues

depth cues availiable to each eye separately

Retinal Disparity

a binocular cue used to perceive depth between two nearby objects; the difference between two images (the greater the disparity, the closer the object)

Linear Perspective

parallel lines appear to meet in the distance

Relative clarity

we perceive hazy objects to be farther away and sharper/clearer objects as closer

PHI Phenomenon

An illusion of movement created when two or more adjacent lights blink on and off in quick succession

shape constancy

we perceive the form of familiar objects as constant, even at different angles

size constancy

we perceive objects of having a constant size, even while our distance from them varies

prosopagnosia

the inability to recognize the faces of familiar people, caused by damage to a region of the temporal lobe responsible for recognizing faces

change blindness

when a stimulus undergoes a change without the observer noticing

interposition

if one object partially blocks our view of another, we perceive it as closer

selective attention ( cocktail party Effect)

the human brain can only devote 100% focus to one task at

Middle ear

chamber between eardrum and cochlea containing 3 bones that concentrate the vibrations of the eardrum on the cochleas oval window

Middle ear 3 bones

hammer, anvil, and stirrup

inner ear

innermost part of the ear , containing the cochlea , semicircular canals and vestibular sacs

anvil

a tiny bone that passes vibrations from the hammer to the stirrup

cochlea

a spiral-shaped, fluid-filled inner ear structure; it is lined with cilia (tiny hairs) that move when vibrated and cause a nerve impulse to form.

eardrum

a thin membrane that vibrates when sound waves reach it.

Eustachian tube

a tube that connects the middle ear to the back of the nose; it equalizes the pressure between the middle ear and the air outside.

hammer

a tiny bone that passes vibrations from the eardrum to the anvil.

outer ear canal

the tube through which sound travels to the eardrum.

pinna

the visible part of the outer ear. It collects sound and directs it into the outer ear canal

stirrup

a tiny, U-shaped bone that passes vibrations from the stirrup to the cochlea.

semicircular canals

three loops of fluid-filled tubes that are attached to the cochlea in the inner ear. They help us maintain our sense of balance

frequency

the number of complete wavelengths that pass a point in a given time

pitch

a tones experienced highness or lowness

frequency theory

the theory that the rate of nerve impulses traveling up the auditory nerve matches the frequency of a tone enabling us to sense its pitch

Sensorineural hearing loss

hearing loss caused by damage to the cochleas hair receptor cells or to the auditory nerves

Cochlear implant

a device for converting sounds into electrical signals and stimulating the auditory nerve through electrodes threaded into the cochlea

Conduction hearing loss

hearing loss caused by damage to the mechanical system that conducts sound waves to the cochlea

Place theory

the theory that links the pitch we hear with the place where the cochleas membrane is stimulated

Gate control theory

pain is felt when a nerve gate in the spine allow pain signals to reach the brain . if the gate is closed, no pain will be felt

drugs, adrenaline , distraction

sensory interaction

the principle that one sense may influence another

Papillae

the tiny bumps covering the surface of the tongue

Taste buds

up to 200 in each papilla

taste receptor cells

between 50-100 that respond to taste molecules

proprioception

determination of your body position in space